With just a few days to go before the release of Avengers: Endgame, there’s a new trailer out marking the occasion. This one is very different than all the previous clips. Instead of hyping the new movie, it mostly looks back at the previous 21 films from the Marvel Cinematic Universe, from Iron Man all the way up through Captain Marvel just a few weeks ago. Then at the end of the clip there’s a few new shots from Endgame, and the now-familiar refrain of “whatever it takes.”

There’s also a line that sounds particularly ominous. “Before we’re done, we still have one promise to keep,” says Captain America. (Tony Stark’s subsequent line about how if they can’t protect the Earth you can be damn sure they’ll avenge it comes from the first Avengers movie.) So what promise do the Avengers have to keep? And done with what? Did they make some kind of Faustian bargain for the power to defeat Thanos? Did they agree to sacrifice their own lives in exchange for the restoration of the other half of the universe?

We’ll find out on April 26, 2019 when Avengers: Endgame finally opens in theaters. Without spoiling any of the rumors floating around about the plot of the film, the fact that this trailer is going out of its way to remind viewers of all the movies that have come before feels very deliberate. (Also: Did you notice the clips from The Incredible Hulk weren’t from that movie? Poor Edward Norton.)

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